Restricted-service telephone-exchange system



Nov. 6, 1928. 1,690,214

, w. w. CARPENTER RESTRICTED SERVICE TELEPHONE EXCHANGE SYSTEM Filed April 27, 1927 11 Sheets-Sheet 1 2// flax ATTORNEY RESTRICTED SERVICE TELEPHONE EXCHANGE SYSTEM Filed April 27, 1927 ll Sheets-Sheet 2 //Vl/E/V7'0/?. WARREN W CARPENTER daww Arron/vs) Nov. 6, 1928. 1,690,214

w. w. CARPENTER RESTRICTED SERVICE TELEPHONE EXCHANGE SYSTEM Filed April 27, 1927 11 Sheets-Sheet 3 Had.

Arm/my Nov. 6, 1928.

W. W. CARPENTER RESTRICTED SERVICE TELEPHONE EXCHANGE SYSTEM Filed April 27, 1927 11 Sheets-Sheet' 4 fia. 4.

' Q /N|/EN70/-?.

VIM/MN W CARPENTER 4 64M Nov. 6, 1928. 1,690,214

- w; w. CARPENTER RESTRICTED SERVICE TELEPHONE EXCHANGE SYSTEM Filed April 2'7, 1927 l1 Sheets-Sheet 5 //vv//r0/?.' mm? W CARPENTER 5y 6% aw Nov. 6, 1928. 1,690,214

W. W. CARPENTER RESTRICTED SERVICE TELEPHONE EXCHANGE SYSTEM Filed April 2'7, 1927 ll Sheets-Sheet 6 MFG/MAL 644 627 Nov. 6, 1928. 1,690,214

1 v w. w. CARPENTER RESTRICTED SERVICE TELEPHONE EXCHANGE SYSTEM Filed April 27, 1927 ll Sheets-Sheet 7 Arrow/7 W. W. CARPENTER RESTRICTED SERVICE TELEPHONE EXCHANGE SYSTEM Nov. 6, 1928,

ATTORNEY Filed April 2 1927 11 sheets-sheet 8 //VV/VTO/?.'

Nov. 6, 1928. 1,690,214

I w. w. CARPENTER RESTRICTED SERVICE TELEPHONE EXCHANGE SYSTEM ed April 27, 1927 ll Sheets-Sheet 9 644, //2/, ///4 //Z3 F/G-Q m; aw

ATTORNEY Nov. 6, 1928. 1,690,214

w. w. CARPENTER RESTRICTED SERVICE TELEPHONE EXCHANGE SYSTEM Filed April 27, 1927 11 sheets-sheet 10 waww Arm/MY Nov. 6, 1928. 1,690,214

w. w. CARPENTER RESTRICTED SERVICE TELEPHONE EXCHANGE SYSTEM Filed April 27, 1927 ll Sheets$heet ll Arm/MY Patented Nov. 6, 19 28.

. UNITED STATES PATENT 1 WARREN w. oanrnnrnn or QUEEN'S VIL GE, new row, .ASSJIGNQR To waste-arr ELECTRIC COMPANY, moonroxmmnn, on NEW YoRK, Y., A conroR-Am'on'or NEW YORK.

im lication filed April 27,

This invention relates to telephone eX- change systems in whichconn'ections are established bymealnsof automatically oper ated apparatus and has for its ObJQCt the provision of improved means for controlling the scope'ofthe service granted to the subscribers. y

t It is customary to group the subscribers linf'es incoming at :a telephone exchange in 10 accordance, with the service to which they are entitled; direct lines, party lines, lines equipped with coin boxes, lines entitled to only restricted service, etc., constituting separate ri1ps. In the past these groupsof 1 subscribers have been served by separate groups of senders. In the case of senders serving subscribers who were entitled to restricted service only, the setting of'the registers for i'estrictedgroups was employed 2 to cause the-connection of the line to an operators position. According to ar-' .rangement there could be only two classes of oflices, those to which the restricted subscribers could be. connected and those to which they could not be connected. In order itodiscriminateimore closely it was necessary to make additional groups and ,providead ditiona'l senders V In accordancewiththe present invention the subscribers lines are grouped in accord anceeriththe class of service to which they are entitled at the 'basic rate and the arrangement is-characterized by the fact that provision is .made in senders, common to all nclasscs of subscribers lines, to record the class of service to which a calling line is entitled and in conjunction with Zoning ;relays which arcrsetincaccordancc with the ofiice code dialed by the calling subscriber, to determine whether the call shall berouted into the Zone into which the subscriber 'has dialed or rerouted to a specialtrunk.

.The embodiment of thezinvention dcscrihed hereinafter byway of example. pro- 45 .vi'des. specifically stated, a coordinate switching system employing senders and markers which are associated with a. calling line and associated district selector for the purpose of controlling the operationof the selector in accordance with the reglstrati'on set :up in the sender from the sub.- scribersidial. The markers are associated with the rlistrict'selectors by means of? a RESTRICTED-SERVICE TELEPHONE-EXCHANGE SYSTEM.

1927. Serial n 186,904.

district frame connector which includes relays individual t'o'eac-h district frame to which the connector has access. Since the group of district frames -is al to the group of lines served thereby, the relay in the frame connector may be employed to identify the class offline over which a particularcall originated. The registration of the ofiice code of'the wanted siibscriberca'izses the operation of a routing relay in the marker and in the case of 'nonlocal offices a zoningrelay' is alsofoperalted. In the case of lines whose service is restricted the joint operation of the zoning relay-and the frame connector relay causes "the release of the routing relay corresponding to the dialed code and the operation of another routing relay which will cause the connection of the subscribers linetota trunk to an operators position. Where the subscribers service islnot restricted no. such cooperation takes place and the routingfirelay functions.

Both the 'gcnerahan d specific-aspects of the invention will hemore clearly understood from consideration of -the following description in connection With'the drawings -in whichfi Fig. l shows the calling subscribers line,

aline switch, a senderselector, a sender and a sender form; o c

Fig. 2 shows a circuit of one trunk going to a district selector; Fig. 3Yshows a-"di'strict selectortswitch';

connector all in diagrammatic selector;

Fig. .5' shows an ofll'ce selectorf; Fig. '6 Shower group of relays the marker for testing the trunks of a trunk r up; i Fig.7 shows the registers ofthe marker; Fig/8 shows the district frame connector and the district trunk connector a 9 shows translator which determines-the routing relay to'be operat ed;

Fig, '10 shows the office frame connector and the oilice trunk connector; Fig. 11 ShOWsthe routing-and zoningre 1ays;an d

M Fig. I12s'hows the manner in which Figs. 11 to lllinchisiv'e should be arranged. uIn general the. system and apparatus emindividu- I ont- Figs. l show's a'trunli outgoing .toan office plo-yedlin thepresent disclose??? are thceam'e as those disclosed in U. S. Patent 1.600.399, granted September 21. 1926 to V. W. Carpenter and reference is made thereto for a more complete showing and description of such a system.

Line 101 represents one of a group of lines entitled to the same class of service. lVhen the subscriber thereat initiates a call the line will be extended through line switch 100 to a. trunk such as trunk 116 leading to one of a group of district selectors serving this particular group of lines such district selector 300. The operation of the line. switch 100 in turn initiates the operation of sender selector 150 to associate an idle sender with trunk 116. When the connection of an idle sender such as sender 170 to the trunk has been completed ground is connected to conductor 21 1 operating relays 200 and 206 in parallel. Relay 206 at its right front contact supplies ground to conductor 211 to hold the line switch operated. Relay 200 in operating opens the circuit of relay 201 and extends the tip and ring conductors from the calling line to the impulse receiving mechanism of the sender. Relays 205 and 212 have also been operated described in the above identi tied patent.

The subscriber now dials the number of the wanted subscriber and this number is recorded in the sender. A record is likewise made in the sender of the group of district selectors to which selector 300 belongs. As soon as the oflice code. represented by the first three digits dialed, has been recorded, the sender connector 160 is actuated to connect the sender with an idle outgoing marker. For simplicity the conductors extending from the connector 160 to the marker have been grouped and are represented by brackets and the heavy dotted line 180. The above mentioned operations also take place in the manner disclosed in the above identified patent.

As soon as the sender is connected to the marker. the sender connects battery to conductor 913. which extends to the winding of relay 908 and ground so that relay 908 operates. The operation of the sender connector 160 also establishes circuits from ground over the front contacts of the operated relays of the code registers of the sender to the windings of the corresponding relays of the marker registers 700, 701 and 702 to transfer the code registrations from the sender registers to the marker registers.

At the same time a circuit is closed from ground over the back contact of relay 911, conductor 950, through sender connector 160, over the back contacts of all unoperated relays of the sender registers and back over connector 160, through the windings of the remaining relays of registers 700, 701 and 702 in parallel to battery. The relays of these registers operate, elosing a series circuit from battery through the winding of relay 910 and thence through the contacts of all the marker register relays in series, over the left back contact of relay 909 to ground at the outer right front contact of relay 908. Relay 910 looks over its left front contact. back contact of relay 912, back eonta't of relay 909 to ground at the outer right front contact of relay 908. Relay 910 in operating closes an obvious circuit for operating relay 911 which removes ground from conductor 950. Relay 911 also operates relay 912 and relays 912 and 911 lock over the left front contact of relay 911 and the back contact of relay 909 to ground at the contact of relay 908. The operation of relay 912 opens the locking circuit; of relay 910 causing that relay to release. The removal of ground from conductor 9.70 permits those marker relays which do not correspond to operated sender relays to release. Let it be assumed that. relays 703, -21, 706, 708. and 712 are held operated.

The next step is to operate the translator 900 from the register relays in the marker to select one or more of the routing relays shown in Fig. 11. each of which relates to a diti'erent one of the groups of trunks outgoing from the district and ofiice selector switches.

The register 700 with the setting given causes the operation of multi-contact relay 991} in a circuit from battery through the winding of said relay, thence through the inner right front contact of relay 704. outermost right front contact of relay 706, inner right front contact of relay 70f). conductor 717. back contact of relay 910. front conta't of relay 912, back contact; of relay 909. front contact of relay 908 to ground. The register 701 with the setting gi en causes the opcratirm of relay 905 in a circuittraccahle from battery through the winding of said relay. thence orcr the middle right back contact of relay 707, inner left front contact of relay 708. the outer right back contact of relay 709. ba k contact of relay 710 to the groundcd conductor T17. Vith the translator 900 set. a circuit is completed from grounded conductor 717 through the right back contact of relay 714. outer right back contact of relay T13. inner left front contact of relay 712. outer right back contact of relay 711, conductor 919. contact of relay 905. contact of relay 903. conductor 951, through the distributing frame 1113 to the winding of relay 1193 and battery. Relay 1193 connects ground over its outer left front contact: to the windings of relays 1106 and 1107.

lVhile the foregoing operations have been taking place the outgoing marker has also been in the act of asso iating itself with the proper group of district selector frames by means of the corresponding one of the frame connectors 800 and 801. lhe instant the sender is connected to the outgoing marker,

' the record set up in the sender of the group to which district selector 300belongs, causes district frame connector relay 609 to be operated. This relay relates to the frame connector 800 and when operated instructs the marker that it must use that particular frame connector for selecting the proper group of district selectors. The other frame connectorrelay 610 similarly relates to the frame connector 801. Relay 609 gives this instruction by closing a circuit for relay 804, which is individual to the marker shown, at

- thedistrict frame connector 800. This circhit maybe traced from battery through the inner left contact of relay 908, conductor 918, right contact of relay 602, contact of *pose may be traced from battery through the ing contact, left "back contact of relay 820,fwinding of relay 8'05 tolgro und. Relay 905 also operates and prevents any other wthence over conductors 821 and633, leit conrelay 609, might winding of relay 804 to ground at the contact of relay 805. Relay 804 operates and locks ina circuitfthrough its left Winding and lock marker from appropriating the frame connector 7 Relay 805 closes an obvious cirunit for the multi-contact relay 806 which extends the various leads from the marker through to the grid wires of the connector The vertical operating magnet 310, in-

difvi'dual to therow -of contacts301 of the selector 300, in which the trunk 116 appears,

is now operated. The 'circuitfor 't-hispurwinding of said magnet, conductor 318, outer right contact of relay215, upper front contact of relay '200, thence over conductor 216 through the sender: selector 150, through the sender connector '1 60, through the cable 180*toconductor719, left bank contact of relay 606,- conductor 632, innerright contact ofrelayBO l to: ground at the front contact of relay 805. lt will be noted that the relay 611 also operates in parallel with the vertical magnet 310. Magnet 310 prepares the con tacts of the vertical =row 301. It also operates :the multi-contactnrelay 809, individual to the switch 300, in a circuit from battery through the winding of said relay, inner frontcontact of magnet310, and thence over conductor 318 to ground-:as above traced.

Relay 809 connects the. grid wires otathe frame connector 800-to the conductors leading to theswitch 300. With fiche .fralineconnector 800 operated, the vertical magnet 3 10 and relay 809 are locked in: parallellcircuits extending through the firanie connector,

tact of relay 603, conductor 720 to ,ground at the inner right contact of relay 908.

Relay 215 is also operated at this time in a circuit frombattery throughits left winding, conductor 217,lowermost contact oitrniagnet 310, contacts of frarne connector 800 "to ground. Relay 215 locks through the left front contact of relay to grounded eonductor 211.

Since the multi-oont-actrelays 808, 809,

etc are each individual to a district selector switch such as 300 the identity of this switch fmay he cstablishediby the frame connector 800 for the purpose of determining which one of the routing'relays shown in Fig. 111 r twill be recalled that.

should be operated. in the present case, both relays 1106 and 1107 werepreparcd for operation. Only oneof -these, however, isneederhwhich is the one that is individual to the group of trunksappearing in the district selector frame 300.

Accordingly, relay 808 has certain :of iits contacts arbitrarily wired to ground, oneof which identifies the district selector frame 300 for this purpose. Accordingly, relay 11-11 is; operated in a circuit traceable from battery through the winding of said relay,

conductor 1012, through thecontacts of the frame connector 800 to ground. Relay llll completes a circuit for operating routing relay 1106 to the exclusion'iof relay 1107.

This circuit may be traced from battery over the inner contact of relay 1111, thence through the windingvof relay 1106 to ground at the front contact of relay 1193. l With relay'1106 operated, relay 6 13 is operated in a circuit from 'battery'through the winding-of the latter relay, thence over the conductor 644 to ground atwtheicontact of relay 1106. Relay 643 Elo'Qks'St-O the grounded conductor 'Z20. Relay 638 is operated in turn in a circuit from battery throughits' winding, outer left contact oi V relay 643, conductor 6455, lefthaclrccontact Y of relay 909, to ground at the contactnof relay 908. Relay 638 serves to delay the notification of the sender to release from the marker until after the ofiice selector district frame it shouldinalre connectionl."

W'it'h. relay 1106'operated, a circuit closed for relay 811, which is individual to. the selected unarker at the trunk connector 802, extendingfrom battery, in-ner lett contact of relay 908, conductor .918,;right contact of,

relay 602, contact of relay ,611, ,condnctor 11114, inner right contact of relay 1106,:conductor 822, rightwindingof relay 811, back contact of'relav 812 to ground. BelaySll locks through its: left Minding-t .--ground i all) series with the winding of relay 812 and relay 812 also operates. Multi-contact relay 813 is operated next in a circuit over contacts of relays 811 and 812. Relay 813 connects the various conductors from the marl-:01 to the common grid wires of the trunk connector 802.

The next. step is to operate the particular one of the multi-contact relays 815, 816, etc, which represents the group of trunks to which the marker is to be connected. In the present case the group of trunks appearing in the vertical row 305 of the district selector is represented by the relay S15 and this relay is operated directly from a con tact of the routing relay 1106 in the inarlier. The circuit therefor may be traced from battery through the winding of relay 815, conductor S32, outer right contact of relay 1106, conductor 1115 to ground through contacts of relays 811 and S19. Relay S15 connect-s the grid wires of the connector 802 to the conductors leading to the test conductors of the several trunks in the pro er group.

Since the multi-contact relay 915 is individual to the row of contact 305 its operation may he made to cause the ()Ptil'tlilflfi of the vertical magnet The circuit for this purpose may be traced from ground through the contact of relay 815, thence through a contact. of relay S13, conductor 825, right contact of relay conductor 634, middle right contact of relay 1106, con- (.lnctor 1013. through the frame connector thence throu h the Winding of magnet 313 to battery. lWagnet 313 prepares the contacts in the vertical row 305 and also operates relay 606 in the marker. The circuit; for relay (306 may be traced from ground through the contact of magnet 313, conductor 319, through the frame connector 800, conductor 827. winding of relay 606 to hat tery. Relay 606 locks over its inner right contact to the grounded conductor 720.

The marker has thus been connected to the district frame and the trunk group outgoing therefrom and the apparatus is now in condition to test the horizontal links in the district switch and the corresponding outgoing trunks. This operation being fully described in the above identified patent. it will merely be assumed that linl: 308 and trunk 4 h are the first to be idle and that in con sequence relays 620 and 622 are operated while relay (32st remains inert. Relay 625 is therefore operated in a circuit from battery through the winding thereof, left back contact of relay (32%, left front contacts of relays (322 and (320 in series conductor 635 through the trunk connector 802 to the distribution frame 824 and returning through the trunk connector to conductor S29. outer right contact of relay 606, left back contact of slow relay 602 to the grounded conductor T20. Relay 62 opens the operating circuits of relay G21 and closes a circuit for horizontal operating magnet 316 from battery through the winding of said magnet, conductor 32-h through the connector 800, con due-tor 8230 to ground at the outer contact of relay (S25. Magnet 316 effects: the connection through the district switch 300, thereby c:-;teudin the trunk 116 to the selected idle outgoing: trunk 402.

This connection having been established, a test is made which involves contact. points on district selector FWltCl] 300 to make sure that the switch is properly operated. For this purpose a circuit is closed from battery through the winding of relay 604. left back ctntact of relay tit-7, thence through the inrer front contact of relay (325, conductor 63?, through the trunk connector 8102. conductor t l (nu-rated contacts of switch 300 to the grounded sleeve condiu'tor 211 of trunk 116. lc ay (301- locks and closes obvious circuits for operating: relays (302 and 603. Relay (M l at its riejht contact opens the circuit of the vertical ma 're 313 which releases. At its left contact relay G03 opens the holding! circuits of the operated test relays in the marker and also opens the holding circuits of vertical magnet, 310 and multi-contact rclay S09.

Relay G02 releases the relays 811 and 812 which in turn cause the release of relay 813. lTelay (302 also releases relay 625 which opens the operating circuit of magnet 3113. In addition, relay 602 opens the circuit of relays SOl and 805, in turn causing the rclease of relay 806. The relay 811 in releasirc releases the inulti-contact relay 816. Thus, the outgoing marker is disconnected from the district frame 300 by the release. of the frame connector 800 and from the group of trunks by the release of trunk connector 802. The connection through the district selector frame 300 is held by the maintained (kl itl'tltltln of horizontal relay 316 which is locked in a circuit from battery through both windings in series. thence through contacts of switch 300 to the grounded conductor 211. Relay (302 also extends ground from conductor 720, over its front contact to the hack contaet'of relay (338. \Yere relay 38 not operated, conductor 660 would he grounded. completing a circuit: through the timing device 730 to the sender to cause the disconnection of the marker from the sender. Since. however. relay 638 is operated this circuit is not closed and the marker remains connected with the sender.

In case a group of trunks leading from the district frame to the otlice frame is larger than a single vertical row of contacts on the ofiice frame can accommodate they may be arranged in two or more sub-grou iis. In order to distinguish the particular subgroup involved, all the trunks of a common subltlt) lll l group are identified by a. characteristic circuit'connecteil toithe contaottof relay 100i] there being, one of these, relays. for each:

trunk, in, the, group. In the present case a ,loiv 1esi,,c(1-11'Ceil01 is connectedto the back Contact, For asecond' sub-group the resistnectio n ance4'01 iwultl'he high, As soon as thecon- 0e ,h l hetl loycr the district frame E300 a ciro t 'ierlosetl,tro ngronnrl through the lbw i V of releyQlOOQ thence over the ring side of tance 401,1111101 back contact trunk 4.02, "thrmi'ghffthe *clistrict selector switch 300, conductor 220, through the send- 1 er selector switch 150 and the sender congrounded condi'ictor'720l hector 1160' to conductor 722, miter haclt con} tact ofirjelay 601, windings of relays 640 and] 641 to battery. since the resistance 401 is, low, both the naiginalrrelayj 640 ancl the re- 1x13 36431 operate. Theserelays lock; to the g'rounpldhondhctor 7 20, Relay 641' operates relay 642 which also looks to COIltliICtOI' 720.

The operation-otjrelays 64:0, 641 and 6 12 initiates the connection of the marker with the ofii'ce selector 500: to which trunk 102; extends. For this purposeacircuit is closed fromgrounlover-j the back contact of relay 1003,,right winding ofrelay 1002, which is individualto the inarHer-inoflice frame con nector 1000, conductor-1014, right contact of. relay! 643, right front contact of. relay 640, left contact of relay 642,1-ig1it contact of relay 607 to hatter'y" over, conductor} 91S. Relay-1002, locks in seriesfwith elay 1003 and the two jointlycause the operation of A multi-contactrelay1004. I

The ertical magnet 509 of theothce se-,

lector switch 500 isnowoperateclfin a circuit from battery; through the winding thereot condnctor 512,,out'cr back contact of relay 400, over the tip of the trunk thronghfthe district selectorswitch, and over conductor 216as previously ti' acegl',throngh the senderfconnector 160to conductor 719',

and thence over the inner leftfront contact of relay606flefti contact of relay 601, con ductfor646, contacts ot'trelay 1002 -and 1003 to ground. Rlayf612'is also operateilin parallel with the circiiit abov'e traced. The magnet 509 prepares] the contacts of the vertical row 502 and also operates the multicontact relay 1006 which is individual to theparticnlar office selector frarne3500l The circliit. for this latter relay may be newt froin. battery through the Winding. thereof,

thence over the contact oflrnagnet 509, to

groundov er conductor 512. The magnet 509*'an(l,relay 1006lock; incircuite through their windings, thence over a path through the ofiice frame connector l000, concluctor 1015, through the left contact of relay 608, left front Contact of Relay '612,Whi0l1 operates when the frame connector 1000l0perates, closes an energizin circnit't'or the relay 1007of' the oflice trnniz' relay 602', to the connector 1001. This circuit may be traced i from ground through tliefbaclt contaetf ot g; ,rela' 1008,, right \vi l ding oi31-e1 y'7,

cont notor 1016,, thence fthr oiigh the inner l right'contact o'fre'lay 1193, contliictor 1 121, '70 g cont-act of relay 612, through theright con;

tactof relay 607' to battery over condii'ctor, I 918. Relay 1007 operatesancljlocksthrough itsleft Winding and the winding ot relay H 1008, and thelatt er relay 1 also 'energizesgis Relays 1007 and, 1008 jointly operate the: Q multi-contact relay 1009. i i Assume that the group of trnnlrs leading; to, the desired o filce appear in the v er-a1;

-"row 504 01' the ofliceselector switch 5O0andj 30 thatr the relay 1017is incliriclnalto this particular group; Relay 1017 accordingly is,

oper atecl in a circu-ittraceah1e from battery T V The vertical ope1iatin magnet 511"isnen't energizedby means ofa circuitfioin b at- 1 tery throughits-winrling, thence over cor-1 ductor 513', through the frame connector 1000,;conchictor 1019, through the initltlle right contact of relay, 1 1 9 3,the1ice over confi" Motor 1123 through the right contact'olf re 1 lay 608,-condi1ctor 647, through contacts of, H the frame connector 1001 togroii with the circuit just traced. The magnet 511pfrepares the contactsin'the verticalroiv 504ancl also operates relay 601111 a'circn'it traceable from battery thi'ongh the Winding of said relay, conductor 648, through the frame connector 1000, to ground atthe contact of magnet 511.

The horizontallinks-505, 506, 507', 508, etc., of the ofiice switch500 and the corresponding trunks of the (outgoing groups are tested by means of the test relay in the marker exactly the same mannerfas tlis h closeclfin' connection with} the district 'seletw t01i30'0l Assume that the ,link -508ancl the corresponding tinnk 514are bgothiclle and that no preceding trunk and its corres ond-j inglinkareboth itllel Accordingly, relays I620, 622 'andj624 are all operated and relay 626 is the firstfone inv the series to remainl deenergiz e'di Relay 627 is nextoperateclin a c rcni't from batterythrough its inding, left back contactflotrelay626;lett'front 0on i tacts-of the test relays, theitce over condnc i tor 635, throughthe o tficetrnnk connector 1001, throi1gh the innerlett'contact oti relay 1017, and rethlr'nlng ovortheicontacts'j oft-he oflice trunk connector, conductor 829, outer right contact 'offrelay 601, lefhcontact oit relay 607, left front contact of relay 602,11

has thus been established and the marker may now be released. This is accomplished by operating relay 650 in a circuit from battery through the winding thereof, left front contact of relay 605, conductor 651, inner right contact of relay 627, conductor :2, through the trunk connector 1001, through the contacts of switch 500 to ground on conductor 103. This circuit provides a test to ascertain whether the oltice frame has completed the connection. Relay 650 locks through its right front contact and operates relays 607 and 608. These relays bring about the release of the office frame connector 1000 and the oifice trunk connector 1001, whereby the marker is disconnected from the oflice switch. Relay 607 also con nects ground to conductor 660 from the front contact of relay 602 thus causing the sender to release the sender connector 160. The outgoing marker is thus disassociated from the sender and restored to common use. The vertical magnets 509 and 511 of the oiiice switch are released and the connection thereover is maintained by the continued energization of the horizontal magnet 515.

The completion of the connection to the called subscriber takes place as described in the above identified patent.

Restricted calls.

It is of course customary to permit subscribers to make calls at the basic rate only over a. limited area and to make an additional charge for calls to offices at a greater distance. It may be desirable to permit certain subscribers who pay a higher basic rate to make calls over a larger area than others. The ofiices are therefore grouped in zones and the subscribers are grouped ac cording to the zones to which they are entitled to be connected at the base rate. The district selectors are made individual to the particular class of service group. Therefore, since the relays, such as relays 80S and 809 in the district frame connector 800. are individual to the particular district frames. it is possible to identify the class of service to which a calling line is entitled by means of contacts on relays 808 and 809 in the frame connector. Zone relay 1193 which was operated in connection with the above traced call represented a zone to which all subscribers had access but which was reached from the oflice selector, relay 1106 controlling the lection of a group of trunks outgoing to an ofiice selector.

Had the subscriber dialed a code such that zone relay 1108 had been operated, realy 1190 would have been operated and the circuits for relays 1106 and 1107 would have been prepared. The operation of trunk con nector 800 is independent of the setting of the registers and takes place at the same time as registration. Therefore when relays 809 and 1108 have been operated a circuit is closed from ground over the contact of relay 809, through the frame connector, conductor 860, outer right contact of relay 1108, conductor 1150, winding of relay 909 to battery. Relay 909 locks over its left front contact to the outer right front contact of relay 908. it its left contact relay 909 closes a circuit from ground over the outer right front contact of relay 908. right contact of relay 909, conductor 960, winding of routing relay 1105 to battery. it. its left contact relay 909 opens the locking circuit of relays 911 and 910 and disconnects ground from conductors (315 and 717. The removal of ground from conductor 717 releases the relays of translator 900 in turn releasing relays 1108 and 1190 and removing ground from the windings of relays 1106 and 1107. The routing corresponding to the code dialed has therefore been cancelled and a new routing set up which leads to :1V special trunk appearing at an operators position.

The functioning of the marker to select this trunk is essentially the same as in selecting any other trunk group, the control being assumed by relay 1103. Therefore these operations will not be described in detail. However, since talking battery is usually supplied, when a connection is tablished to an operators position, from the operators cord, means is provided for disconnecting repeating coil 202. For this purpose a circuit is established from ground over the middle left contact of relay 1106 to conductor 833, through the frame conductor 800, conductor 327, middle lower contact of magnet 310, conductor 221, upper winding of relay 201 to battery. Relay 201 locks over its inner upper front contact to conductor 211. It disconnects the tip and ring conductors incoming from the subscribefls line from the repeating coil 201 and extends them directly to the tip and ring conductors outgoing to the district. selector.

From an inspection of the circuits it will appear that relay 1191 represents a zone to which, the subscribers corresponding to relay 809 would have free access. The subscribers belonging to the group represented by relay 808. however, are restricted from making calls to the zone corresponding to either meats relay, 1,108 013.1191. It is t herefore possible grades oi service as desired.

bytt-his arrangementto provide as many Whatisclaimcd is: 4 L. In a a telephone system, subscribers] lines 0i aplurality of classes,,a control device for controllinw the, establishment of connections frpmall c asses of said lines, means for associating'lsaid control device witha calling, line, Selective means in said, device undelnthe contIfOllOf, said'calling line, means, for identifying. the, class to which said calling, line be; n s, nd means unear hs j t ont l i.

said selective means v and said identifying means to determine the manner in wh ch said onnect on al he; c mp te 2. In a telephone system, subscribers lines.

of;;a,, plu1:ality of classes, a control device identifyingthe classto whichsaid calling line, belongs, antltmfi ans under the joint con-- trol of-said recordingmeans'and saididentr rying means to,determine whether tornot,

said connect-ion: shallabe completedto the wanted ofiice; a

, ,-)In,a telephone system, subscribers? lines, of a pluralityof classes, an OPGliltQlZSPOSi;

tion, a control device for-controlling, the

establishment of connections, from all classes of said lines, means, for associating said control device with a calling, ,line, means in saiddevicennderthe control of said calling line for recording the. desi'gnatiqn of a t dioffieem s. o nti y t e clas towhich said calling linehelongsandimeans under the joint, control of said recording means and: said identifying means to determine whethersaidgconnectlons shall be com pletedqto the wanted office or, tosaid opera ators position. a

4. a telephone system, subscribers? lines, of a plurality, of 2 classes, a control, deyice for, controlling the establishment, of conned tions from all classes of said lines, means foressociating said control device with call ng line,means under the, control ofsaid,

cal-ling line, for recording the designation ,of l V a wanted office, means operated in accordance 1 w lh said record for cont-rolllng the extension of a connection from sa d calling line to. said;

oflice, and means under, the control} ot'lsaida recording-means efi'ectlvetif the calln1g=sub scribers line is of a particular class to render,

a said extension controlling. means inefiectivc.

5. In: a telephone system, subscribers lines of a plurality of classes, an operators posis, tion, a control deyice for controlling the establishment-of connectionsfrom all classes ofrsaid lines, means forassociating said con trol deyice witlracalling line, means vunder ,operatingfother means for controllingcthe 7 or other oflices, a controllingidevi ce at se one 'oflice, common to all, qroiips of lines,

the, control of calling, line,fiorginecording d s a i n, f a Wanted e i ei aaes operated inv accordance, with sai'clTre Qrd f n, controll n the extens1on ofya QQIlflgCfilOilg:

r m: i c l in i e t s id ce, an lIF means under the control of said recording, fii ll$ e fect i've -i i' the calling s1 liscrilj ei f ling;

is of a particular class to render said ext-en.- sion controlling means lllElfQQi-lVG and for extension of said connection to said opera ators position.

6. Ina telephoneexchange system, a, rality of ol'fices located in a plurality oi 7 zones, subscribers lines terminatingat oneQ of; said Qllicesand grouped according tothe, zones to W-hich they are ermitted to lmye; access, selective switches v on extending con nections from said lines to-Jinesin,thegsa neg one common to groups o'f lines a. plurality of routing relays'in sa d dance, means for operating one of, sa d;; relays in accordance with the zone in which the.

wanted ofiice lies, means, operatiyeunden the, 90 control of said relay, if; said callingg liner-be longs to certain groups, to direct the, opera tion of said switches, and means efiective said calling line belongs, to, other groupsgto release said relay and to operate ardifierenty relay. 7 j J 7 In a telephone exchangetsystem, a plu rality of ofliceslocateds in, a, plurality of, zones, subscribers? lines terminating at one oi said offices and grouped according toathe, zones to "which they are permitted to have, access, selective switches for extending; connection from said linestollines inthe, same or other, ofiices, acontrolling; device at said 7 means for setting up a registratiqnlon.said..

device in accordance, with the designation of a wantedoflice, means operative in accordance with said registration to dircct the opera tion of said selector switches, means efiec title if said calling line belongs to certain groups to complete the connection to 1 the wanted office, and means effective if said calling line belongs to other groupsto cancel said registration and to set up a diilerent registration. 7 r a 8. In a telephone, exchange systempaplucontrolling device at said one oflice common I ,v

to all groups: of lines, means fonscttirw up a reg stration in accordance. Wltll: the des1gnation of'a wanted ofiice, meansoperative in;

accordance withsaid f registration, to, d i1'ect;

the operation of saidselective swatches, "Q a rality ofofiices located in a plurality ot means effective if said calling line belongs to certain groups to complete the connection to the wanted ofiice, and means efiective if said calling line belongs to other groups to cancel said registration and to set up a registration to direct the operation of said switches to extend the calling line to said operatofis position.

9. In a telephone exchange system, a plurality of oilices located in a plurality of different zones, subscribers lines terminating at one of said oflices and grouped according to the zones to which they are permitted to have access, selective switches for extending connections from said lines to lines in the same or other offices, a controlling device at said one oilice common to all groups of lines, means for setting up a registration on said device in accordance with the designation of a wanted oilice, means operative in accordance with said registration to direct the operation of said selector switches, means in said device for identifying the group of subscribers to which a calling line belongs, and means under the joint control of said registration and said identifying means to cancel said registration and to set up a diilerent registration.

10. In a telephone exchange system. a plurality of oilices located in a plurality of different zones, subscribers lines terminating at one of said ollices and grouped accord ing to the zones to which they are permitted to have access, selective switches for extending connections from Said'lineg to lines in the same or other offices, a controlling device at said one office, common to all groups of lines, means for setting up a registration on said device in accordance with the zone in which the wanted oflice lies, means operative in accordance with said registration to direct the operation of said selector switches, means in said device for identifying the group of SUlJSClil'lClS to which a calling line belongs, and means under the joint control of said registration and said identifying means to cancel said registration and to set up a different registration 11. In a telephone system, subscribers lines of a plurality of classes. selector switches for extending connections from said lines, means for connecting a calling line to one of said switches, a control device common to all classes of said lines 'lor controlling said switch, means for associating said control device with said switch, selective means in said device under the control of said calling line, means in said device under the control of said associating, means for identitying the class to which the calling line helongs, and means under the joint control of said selective means and-said identifying means to determine the manner in which said connections shall be completed.

12. In a telephone system, subscribers lines of a plurality of classes, selector switches for extending connections from said lines, means for connecting a calling line to one of said switches, a control device common to all classes of said lines'l'or controlling said switch, means for associating said control device with said switch, means in said device under the control oi said calling line for recording the designation of a wanted oliice, means in said device under the control of said associating means for identifying the class to which said calling line helongs, and means under the joint control of said recording means and said identifying means to determine whether or not said connection shall be completed to the wanted ofiice.

13. In a telephone systcn'l, subscribers lines of a plurality oi? classes, selector switches for extending connections from said lines, means for connecting a calling line to one of said switches, an operators position. a control device common to all classes of said lines for controlling said switch, means for associating said control device with said switch, means in said device under the control of: said calling line for recording the designation of a wanted oliice, means in said device under the control of said associating means for identitying the class to which said calling line helongs, and means under the joint control of said recording means and said identifying means to determine whether said connection shall be completed to the wanted ollice or to said operators position.

14. In a telephone system, subs-:crihers lines of a plurality of classes, selector switches for extending connections from said lines, means for connecting the calling line to one of said switches, an operalors position, a control device common to all classes of said lines for controlling said switch, means for associating said control device with said switch, means under the control of said calling line for recording the designation of the wanted oilice, means operated in accordance with said record for controlling the extension of a connection from said switch to said oilice, means under the control of said associating means for identifying the class to which said calling line belongs, and means eliective it said calling line is of a particular class to render said extension controlling means ineffective, and for operating other means for controlling the extension of said connection to said operators position.

15. In a telephone exchange system, a plurality of ollices located in a plurality of zones, subscribers lines terminating in one of said ofiices and grouped according to the zones to which they are pern'iitted to have access. selector switches for extending connections from said lines, means for connect- Inn ing a calling lineto one of said switches, a control device at said one ofilce common to all groups of lines, means for associatlng I said control device with said switch, a plusaid switch to select one route, and means under the control of said associating means,

effective if said line belongs to other groups to release said relay and to operate a different rela to direct the operation of said switch to select a different route.

In Witness "whereof, I hereunto subscribe my name this 19th day of April, A. D. 1927. i

WARREN W. CARPENTER. 

